Muffler.



A. R DORROH.

MUFFLER.

APPLICATION FILED OCT. 3, 1917.

1 ,2'73, 1 59. v Patented July -23, 1m

rarnn QFFXGEO ALFRED IR. DORROH, OF WASHINGTON, DISTRICT 01 CQLUMBIA.

MUFFLER.

Specification of Letters Eatent.

Patented July 28, T9918.

Application filed. October 3, 1917. Serial 1T0. 194,537.

, such as emanate from steam and internal combustion engines, and the object thereof is to silence the delivery of said fluid without increasing the back pressure.

The noises produced by unmuffled discharges of exhaust fluids are largely due to the static condition of the air against which these exhaust fluids impinge, and also to the concussion produced by successive discharges which, at the moment of delivery, are still concentrated and'moving at a high velocity.

It has been proposed to use mechanical,

baflies to blend these successive increments of exhaust fluid into a single retarded cur rent, so that they will be delivered in a spent condition, but, in so far as 1' am aware, no one has heretofore attempted to mix and expand said increments prior to their final delivery to the atmosphere, or to prepare the atmosphere for the reception of the exhaust fluid, and especially not as I propose, by rotating or otherwise setting the air in motion adjacent the discharge outlet in order to lessen the resistance to, and soften the impact of the discharge fluid.

One embodiment of my invention consists 'of a mixing chamber of truncated conical form having an inlet at its smaller end, the larger end being freely open' for the discharge of the exhaust; of power driven rotary fans of successively increased diameters, disposed within this chamber, and operating to mix the separate increments of the exhaust, and blend them into a single rotary current of large volume and relatively low velocity; and of a power driven air propeller for creating rotary air currents at.

the larger end of the mixing chamber, which parallel the aforesaid rotary exhaust current.

impulses and the delivery of an expanded and relatively sluggish rotary current, tend to reduce the force of the impact of the exhaust fluids against the outside air. The propeller for removing static air from the vicinity of the exhaust, is also operative per A so, for its association with any of the known exhaust devices will greatly modify the noise of the exhaust.

The accompanying drawing shows one form of my invention, but it will be understood that I do not limit myself to that particular form, inasmuch as modifications falling within the scope of my invention may be employed.

Figure 1 represents a side elevation of an internal combustion engine equipped with my device.

Fig. 2 shows one form ofsupporting means for said device.

Fig. 3 represents the propeller for the air.

Fig. 4: represents a plan view of the device v with the top removed.

1- is an internal combustion engine, 2 the exhaust pipe thereof, and 3 is my improved device. This device consists of a frustoconical chamber 4 composed of two parts 5 and 6, each of which is flanged at 7, the flanges being provided with perforations through which securing bolts 8 are passed. The chamber may be supported from the floor 9, of an automobile or any other suitable support by means of hangers 10 set into coinciding notches 11 in the edges of the halves of the chamber.

Each hanger has a part 12 constituting a bearing for a shaft, and 13 is the upper member of this hearing.

Extending longitudinally through the chamber is a shaft 14: mounted in the bearings 12, 13 of the respective hangers, which bearings are to be provided with anti-friction balls and raceways for said balls.

The shaft 14 carries fans 15, 16' and 17, which are of successively larger diameters. These fans may be secured to the shaft 14 in any well known manner.

The chamber a is provided with a cylindrical portion 18 which telescopes over the exhaust pipe 2 with which it is connected, and the cylindrical portion 18 is connected to the chamber 4 by an intermediate tapering section 19. The end of the shaft proximate the exhaust pipe 2 has a conlcal end 20, which acts as a spreader for the exhaust current.

35 1 acting upon and moving air adjacent there- Mounted on the shaft 14 in proximity to thelarger end of the chamber 4, which is freely open, is a propeller 21 having plates 22. This propeller is provided with sprockets 23 Which intermesh with the links of the driving chain 24:. 25 is a propeller shaft diven by the engine 1, and having thereon a sprocket-wheel 26, with which the chain 24 engages. J Y

The blades 22 of the propeller 21- are constructed and arranged to impart a rapid rotary motion to the body of air just outside of the freely open end of the chamber 4, so

- that the outflowing helical current of exair. This reduces or modifies impact to such haust fluid will take a course that is substantially parallel With that of'said "body of an extent as to render the exhaust practically noiseless. It will furthermore be understood that the propeller 21 acts also to force the air away from the open end of the chamber 4 and this fact also contributes to the silencing of the exhaust.

Having thus described the invention, what is claimed as new is 1. The combination with a motor, of a chamber for receiving therefrom and expelling exhaust fluid, and means associated with said chamber for directly acting upon and moving air adjacent thereto, independently of the action of the exhaust fluid.

2. The combination with a motor, of a chamber for receiving therefrom and expelling exhaust fluid, and an air propeller associated with said chamber for directly to, independently of the action of the exhaust fluid.

3. The combination with a motor, of a chamber for receiving therefrom and expelling exhaust fluid, a fan. within said chamber, and means associated with said chamber for directly acting upon and moving air adjacent thereto, independently of" the action of the exhaust fluid.

4. The combination with a motor, of "a chamber for receiving therefrom and expelling exhaust fluid, a fan within said chamber, and an air propeller associated with said chamber for directly actin upon and moving air adjacent thereto, in ependently of theaction of the exhaust'fluid.

5. The combination with a motor, a single continuous flaring 'chamber for receiving therefrom and expelling exhaust fluid, 1

fans of successively increased diameters within-said chamber, and additional means associated withsaid chamber for moving air adjacent thereto,independently of the action of the exhaust fluid.

6. The combination with a m0tor, a single contlnuous flaring chamber for receivmg therefrom and expelling exhaust fluid, fans of successively increased diameters within said chamber, and an air propeller associated with said chamber for moving air adjacent thereto, independently tion of the exhaust fluid. j

7. The combination with a fluid pressure motor, means for receiving therefrom and delivering exhaust fluid, and additional means for reducing the normal impact of the exhaust fluid against the adjacent air.

8. The combination of a fluid pressure motor, means for receiving therefrom and delivering exhaust fluid, and additional means for moving and thus reducing the normal impact of the exhaust fluid against the adjacent air.

9. The combination of means for receiving, mixing and delivering successive increments of exhaust fluid, and additional means for moving the air into which the exhaust fluid is delivered.

10. The combination of a fan for receiving, mixing and delivering successive increments of exhaust fluid, and additional means for moving the air into which the exhaust fluid is delivered.

11. The combination of, fans of successively increasing diameters for receiving, mixing and delivering successive increments of exhaust fluid, and additional means for moving the air into which the exhaust fluid is delivered. 4

12. The combination'of a flaring chamber, having an exhaust fluid inlet at its smaller of the acend, and a free outlet at its larger end, of

' tively large outlet opening, and additional means for propelling the air adjacent said outlet opening.

15. The combination of an engine, a mixer for the exhaust fluid delivered thereby, a propeller for the air adjacent the discharge opening of-said mixer, and meansv for driving said mixer from said engine.

16. The combination of an engine, a mixer havingfans of successively increasing diam-- eters, a propeller for the ,air adjacent the discharge opening of said mixer, and means for driving said mixer from said engine.

17. The combination of an engine, having a shaft, a sprocket wheel on said shaft, a further shaft, a mixing'device and anair propeller mounted on said further shaft, said air propeller being provided with sprockets, and a chain for engaging said sprockets.

18. The combination 0ft shaft having a spreader at one end thereof and carrying an air propeller at the other end thereof, and an intermediate mixing device also carried by said shaft.

19. The combination of a source of exhaust fluid, means for giving to said fluid a rotary motion, and means for rotating the air against which said exhaust fluid impinges.

20. The combination of a source of exhaust fluid, fans of gradually increased diameter for expanding and giving said fluid a progressive rotary movement, and means for rotating the air against- Which said exhaust fluid impinges.

21. The combination of a source of eX- haust fluid, and means for moving the adjacent air in substantial parallelism With the exhaust fluid current.

In testimony whereof, I affix my signature.

ALFRED R. DORROH. 

